Sister-hook snatch block



Patented Nov. 21, 1922.

'Unit-so sTATEs 1336343 ?ATENT OFFHCE,

SAHEORD D. E IAIB, OF SAN' FBANOISGO, GALIFORITIA.

grame-noon WATCH smerr.

Application filed .Tune 29, 1521. Serial Io. 481347.

To all whom it may concam:

Be it' lmown that I, Sema!) D. Ian CLAIB, a citizen of the United States, residing at the ;city and 'county of San Francisco and State? of- California,` have inventednew and usefulImprovements in Sister-Rock Snetch Blocks; of which the following is e specification.

This invention reletesto snnteh blocks and espcisll to blocksof the sistenhook type.

One e the obj acts of the resent inventon isto generally mprove en simplify blocks of the character described to reduce the cost of menufecture without lessening strength sud durability, end to provide e structure by which accidental release of the cehle will be revented. v

other object of the invention is to entonsticelly interloclr and 'reinforce the sister books so as to strengthen the same when a hee. pull is being exerted.

Furt er objects will heroina-fier appear.

The inventon consists of the parte and the construction' and combinetion of pflItS es hereinsfter more fully described' and claimed, having reference to the eccompenying drewin s, n which:

re 1 is e side elevetion of the block pertelly in section. i

Fig. 2 is a, central, longtudinsl, transverse section.

Fig. 3 is a, psrtisl plan view of the block showing the menner in which the sister books ere interlocked and renforced.

Referring to the drewings in detsil, there is illustreted. e snetch block of the sister hook type, which consists of a pair of side pletes 2 and 3. These side pletes are identical in shepe and constrction and each plote is substetially semi-circular, as shown i in Fg. 1. The upper end of each plate terminstes in e book portion 4 and these hooks ure adapted to register and inte-lock, as shown in Figs. 1 and 3. The interlocking feature is cccomplished by forming e lug 5 on the heavy end of each book which is edapted to enter e race& 6 in the lflter end of each book, i. e., the books teper m end to end as shown at 7 thereby forming e heavy and light end. The purpose of interlooking the hooks is hereinefter described.

For the purpose of securing the side lates 2 and 3 and for msintaining e prec atermied spacing between the same a shive pin 8 hes been provided. This pin is provic ed with a reduoed thresded extension .at each 'ployed is very small.

end as indicnted at 9 and 10. These extensions form shoulders 11 with which hubhke projections 12, formed on the side pletes, areadapted to en e, i. e., engsgement of the hub portions o 'the annuler shoulders 11 formed on the shive ins limits the inward movement of the si e plates and thereby meintins 'predetermined spacing between the same, the side plates being Secured on the pine or on the reduced extensions 9 and 10 by means of e nut 13 at one end and b means of `a. nut 14 at the 'opposite end. This` nut is extended and exterorly threaded as nt 15 to receive a coupling 16, the enter end of which is closed by means of a plu 1-7, the couplin 16 and the plug 17 formmla grease cup y which grease s automatic& y supplied to the pin 8 and e shive 18 journeled ther-con, i. e. a central opening. or passage 19 is formed in the in which communicates with the grease c amber formed within the eou ling 16, the central passage 19 being exten ed as at 20 to supply greese to the exterior surface of the pin and thereby lubricste the shive 18. The shive proper ia' provided with e hub 21, the length of which is slig'htlv less than the distance formed between t e 'Umer faces of the hubs 12 formed on the side plntes. A free running fit is thue maintained between the side plates and the shive and letersi movement of the shve is prevented as the clearsnce em- The exterior surface of the shive is groovecl end sheped as at 21" to conform wth the eshte employed and the inner faces of the side letes 2 and 3 ere recessed as at 22 to partis y overlep the exteri'or surface of the shive, thue preventing pinching of the cable or jmmm of the same between the shve and the si e plates. In fact the clearence between the side plates and the peripher; of the shive ceused by the over-henging lips or flenges 23 is so small that entrance of the ceble 24 between the 'side plates and the shive will be impossible.

The side plates are freel turnable on the reduced extensions 9 and 10 of the shive pin 8, and it is thue possible to se &rate the hook portions t. This is obviou y e great advantage ss it permits easy insertion or removal of the cable with relation to the shive whenever required. The overlapping and interlocking of the books is also an obvious advantage as it first of all forms a, guerd above the shive which prevents jum mg or accidenta-l removal of the cable wit relation to the ehive end. the side letes. Secodly, inte-locking of the books y means of the l s of importanceas it ties or secures e li t end of each book with rele- 5 tion to the eevy end of the o posite book.

's is im ortent as it preven sepamting when the ooks are placed under e. heavy strain or pull.

Another important feature is the provision off a cupesueh ae shown, 'i. e., hev standard pipe fittin are em Ioyed which may be repleeed ilost or amage'd and whch can stand heavy and rough usege be'- fore'tl'ey u'e"so damaged that eplaeement Will be necessary.

`While certain features of the present nventon are' more o less specifieelly' lhs trete& lc'wish it ndergttoodtthat cha in sha e eig` an con ruc ion may' e d to wth'in the scpe of the apfended elim. Similarly that the 'materia 'finish of the several parte employed s and may be entis:

y on the eheave pin; hu'b -like the experience and judgment of the A snatc'h block -'eomprising 'a of side plates, each having an extension terminatmg in a. hopk-*likegprojectom ech hook having a active being edepted to receive t e respec- 'the hoekstogetherp in nluwing reduoed end poravng a hub po tion mounted pertione'on eeeh of the side pletes,' each one of whchhes -an nwerdly extending ennule-gfla subtantiell'y peralle! with the ax`e'nf t: pin and ada-pted to= enelose the end^portions of the sheave `hub `-md'- have e; tuning-'bea thei-een, nuteon the ei'd' entium of to retain the in poetion, the inside'of each sidefipla being' -recessed to pertielly l se uppeside flerd outwerly from ,the e of the receeses, the side pletes and heoks being free of obstructions 'oventhe sheve to provide a relatively leng, unobs'tructed' 'open space from thelook ebovethe' If `end recesses to the sheave' when the h dededs are opened or closed.

SANFRD D. LE emm 

